A discussion forum contains topics of conversation, and messages relating to those topics. Typically, each message identifies a participant in the forum and includes message text and other indicia, such as when the message was posted. Other users can respond to an “original” message by clicking on a “reply” button or some other graphical element, and posting their own thoughts on the message or on the topic in general. Response messages may be embedded under corresponding original messages, resulting in a message hierarchy that is accessible to users of the forum. Alternatively, a “flat view” may be presented, in which there is no message hierarchy.
A message list is typically displayed in a viewport, which is a user interface (UI) generated by a Web browser. The size and shape of the viewport can be changed. Nevertheless, the list of messages in a forum is often too long to fit in a viewport. Typically, only a small fraction of the entire message hierarchy is visible from the viewport. Users therefore scroll through the list of messages, and may read, or ignore, messages that appear in the viewport.
It may be desirable to identify which messages in a discussion forum have been read. Doing so enables a sponsor of the forum to identify subjects that have generated a certain amount of interest, and to direct forum readers to content (e.g., Web sites or other forums) that provides more information on those topics.
One way to identify which messages in a discussion forum (or any other computer-generated message list) have been read is to associate a graphical element, such as a checkbox, with each message. A user may interact with the graphical element to indicate when the user has read a message. For example, a user may place a check in the checkbox.
Another way to identify which messages in a discussion forum have been read is to identify messages that have been loaded into a user's browser for, e.g., individual display. In this type of system, it may be assumed that all messages that have been loaded have been read.